IntroductionThe Artemia gill-footed crustaceans have gained the popularity in many countries. Now the cyst consumption of Artemia around the world makes about 10 thousand tons per year [1, 2]. Within the last two decades the need for products of an aquaculture annually increases by 5-10% that assumes also an increase in demand on Artemia. Now in the world seven species of Artemia crustacean are discovered, and all of them treat valuable food objects for trade species of fish and other hydrobionts [3].Kazakhstan possesses 10-15% of world reserves of Artemia, the production limit of Ar-temia cyst from the Republic reservoirs for 2019 is set of 1 492.81 tons (limit/quota). The main part of the specified volume is made by the lakes of the Pavlodar region (1 116.0 tons per year). At the increase of the mineralization of water, when the reservoirs are drying or freezing, Artemias form the diapausing ranges - cysts who are beyond all bounds in a condition of temporary physiological rest. The ability of cysts to restore activity in favorable conditions defines the broad prospect of using them as starting live forages at all seasons of the year. Artemia is widespread worldwide and inhabits reservoirs of continental and sea origin with a range of salinity from 20 to 340 g/l. It differs in high and rather stable contents in a protein body - up to 70% of a protein in solid of a crustacean, the considerable level of irreplaceable amino acids, hormones, carotenoids, vitamins, valuable fatty acids. Besides, having a wide variety of physiological, biochemical, morphological properties in separate populations, in general Artemia possesses the well expressed by adaptive fitness to changes habitat conditions. The development of a bioresource of cyst Artemia in salty reservoirs of Kazakhstan, maybe, one of the main directions of development of domestic production of starting bioforages of water origin for needs of fish breeding and aquaculture. There are little works on studying the biology and ecology of Branchiopoda crustaceans living on extensive space of Kazakhstan. Scarce reports or incomplete data can be met in works [1, 2, 4, 5]. In reservoirs of Kazakhstan Artemia is identified as Artemia parthenogenetica by molecular and genetic methods [1]. The purpose of works was to carry out the analysis of hydrological, hydrochemical indicators and stocks of Artemia cyst and crustacean in the Karabassky gulfs of Pribalkhashye. Material and research methodsIn 2021 we have surveyed the state and efficiency of Artemia populations in 5 lakes of Karabassky floods of Pribalkhashya. Determining the water key parameters, collecting and processing hydrobiological material were carried out according to the standard techniques [6–11]. Tests of plankton with Artemia and cysts were selected by the Apstein's network and fixed by 40% formalin. Statistical processing of biological data is executed by the Microsoft Office and Excell applications. The coordinates were determined with the help of the GPS navigation system - the Garmin navigator (Taiwan). The studied reservoirs have the general name Karabassky floods (the system of the lakes Zhantelikol), in this regard further we used numbering of reservoirs. The coordinates of the studied lakes: the 1 lake - NL 46028ʹ23ʺ, EL 76015ʹ08ʺ; 2 - NL 46028ʹ46ʺ, EL 76015ʹ20ʺ, 3 - NL 46029ʹ39ʺ, EL 76017ʹ01ʺ; 4 - NL 46030ʹ08ʺ, EL 76029ʹ23ʺ and the 5th lake - NL 46030ʹ46ʺ, EL 76022ʹ55ʺ.Results and discussionThe hypergaline (salt) lakes of the Karabassky floods in the Karatalsky district of the Almaty region. Reservoirs are located at the altitude from 337 to 339 m above sea level. The area of a water mirror of the lakes, which are a part of the Karabassky floods is 10 000 hectares, from them 730.7 hectares were examined. The main characteristics of model lakes of the Karabassky floods are presented in Table 1.Table 1 Characteristic of lakes of the Karabassky floodsPlace of collectingAl-titude, mArea of the reservoir, haLength, kmGreatest width, kmCoastline length, kmMaximum depth, mAverage depth, mWater mass volume, m3Volume of “residential zone”, million m313381.00.220.060.580.80.40.0040.00323380.20.050.040.160.80.30.0010.00133378.60.440.321.611.00.40.0340.029433712.00.580.331.970.70.30.0360.0315337128.62.941.1711.721.10.50.6430.545The maximum depth in the reservoirs is from 0.7 to 1.4 m, the average depth makes no more than 0.6 m. Food of the reservoirs is generally carried out due to the spring snowmelt and atmospheric precipitation, As well as due to the water area of lakes. Besides the food of reservoirs, the significant role is played by the waters of Lake Balkhash, which get to lakes through underground soil. The coast of the majority of reservoirs are high, in some cases abrupt, up to 7 - 10 m high. The bottom is dense, sandy, rarer clay with impurity of gray silt, the power of silt deposits is about 0.2 m. The water mineralization in salt lakes of the Karabassky floods made from 66.55 to 179.25 g/dm3 that is the favorable environment for existence of a Branchiopoda crustacean - Artemia and existence a cyst. The ion-salt structure of lakes of the Karabassky gulfs, as of 2021 is presented in Table 2.Table 2 Ion-salt composition* of the lakes of the Karabassky gulfs, 2021Sequence number of the reservoirCa2+, mg/dm3Mg2+, mg/dm3Na++K+, mg/dm3SO42-, mg/dm3HCO3-, mg/dm3Cl-, mg/dm3Mineraliza-tion, mg/dm3198.0462.010 550.01 432.05 185.048 825.066 552.02870.011 142.019 225.027 223.03 660.0107 332.0169 452.03225.0795.015 750.01 873.06 405.047 387.072 435.04801.618 775.035 650.335 061.92 440.086 522.4179 251.15480.917 664.035 359.332 660.41 830.077 338.3165 332.9* Using the Salinity Refractometer S / Mill Cat.No/2441.During the researche water temperature in a blanket (0.5 m) was 23.0-24.0 °C. The pH value was 8.0-9.5, which indicates the alkaline nature of the environment. The transparency of water was within 0.3-0.4 m. As for the hydrochemical composition of water and indicators of titrimetric researches, the concentration of the main ions of water (К+, Na+, Mg2+, Ca2+, Cl–, SO42–, HCO3-) was quite high. By the received results according to the accepted classification [11] the water in all studied reservoirs was salty. The largest mineralization value was noted in lakes No. 2, No. 4 and No. 5 – 165 332.9-179 251.1 mg/dm3. At the essential fluctuation band of total amount of salts in the water of the surveyed lakes No. 2, No. 4 and No. 5 in ionic structure everywhere prevailed chlorides (77 338.3-107 332.0 mg/dm3) and sodium ions (19 225.0-35650.3 mg/dm3). The water structure of these lakes belongs to a chloride class of group of sodium with the increased content of sulfates [9, 10]. It is known that with growth of a mineralization the relative maintenance of ions of HCO3 decreases, and maintenance of ions of Cl–, SO42–, Ca2+, Mg2+, Na+, K+ increases. The water in lakes No. 2, No. 4 and No. 5 is characterized by high degree of rigidity, relatively to the lakes No. 1 and No. 3, where the ion- salt composition of water show an average rigidity. The value of water mineralization in all lakes belongs to the category of brines.The population of Artemia crustaceans in lakes No. 1, 2, 3, 4 and 5 of the Karabassky floods is presented by bisexual race, in other reservoirs females and cysts prevailed. The quan-tity of males was almost equal to the quantity of females in a ratio 1 : 1. Only in lake No. 5 the number of males was 3 times less than females. The nature of development of Artemia populations, maturing and representation of age stages in July and August, 2021 considerably differ in lakes No. 1, 2, 3, 4 and 5. In all reservoirs all age maturities except for lake No. 5, where Artemia nauplius stage were absent. It is known that in typical bisexual populations of Artemia the share of males, as a rule, always exceeds 30%, averaging 42.4% [6, 12, 13].The most part of the Artemia reservoirs of Kazakhstan are characterized by existence of Artemia parthenogenetica populations with the absence or extremely small presence of males. A significant number of males can indicate the tension of an ecological situation in the reservoirs and the aspiration of population to increase survival and resilience of posterity. In the reservoirs there are all age maturities of crustaceans. At the same time, the basis of Artemia populations in all lakes is formed by the youngest stages - the nauplius, creating 53-86% of total number of Artemia. The mature individuals during this period are few - 15.2%. And the ratio of mature and immature parts of the population in a coastal part of lakes No. 2 and 3 made 1 : 50. In lake No. 1 and in the center of lake No. 2 the ratio was less – 1 : 6. Among females there prevailed oviparous, with fertility from 15 to 80 eggs in the ovisacs. The distribution of quantitative indices of uneven-age stages of Artemia are presented in Table 3.Table 3Distribution of quantitative indices of uneven-age stages of ArtemiaLacesFemales without cystsFemales with cystsMalesNaupliya (larvae)JuvenilePredadultTotalNumber, thousand copy/m3July, 2021№ 10.030.120.101.50–0.041.79№ 2 (coast)0.03–0.052.500.830.013.39№ 2 (center)0.830.321.218.333.331.6715.69№ 30.010.170.165.500.020.506.36June, 2021 years№ 41.02.02.57.4012.203.0028.1№ 52.31.01.0–2.001.607.9Biomass, g/m3July, 2021№ 176.80452.40276.00255.00–68.401 130.4№ 2 (coast)76.800.00138.00425.00458.3317.101 115.23№ 2 (center)2 133.301 206.404 600.001 416.671 833.332 850.0014 039.7№ 325.60640.90441.60935.0011.0855.002 909.1July, 2021 years№ 42 560.07 400.006 900.001 258.006 710.05 130.0029 958.0№ 55 888.03 770.002 760.000,001 100.02 736.0016 254.0At the end of August in lakes of Karabassky floods No. 4 and 5 the characteristics of Artemia populations were different. The ratio of the mature and immature parts of populations changed towards increase in a share of the mature crustaceans and made 1 : 4 in lake No. 4, and 1 : 1.2 in lake No. 5. The oviparous females here during this period were few and had eggs in the ovisaces in a germ state. The fertility of Artemias during researches is presented in Table 4.Table 4 Fertility of Artemia during researchesResrvoirFemales, exempl./m3Fertility exempl./m3Cystes, exempl./m3June, 2021 yearsLake № 112015500Lake № 2 (coast)008 330Lake № 2 (center)32080830Lake № 3170702 500July, 2021 yearsLake № 42 000501 000Lake № 51 000601 000From Tables 3 and 4 it can be seen that the level of quantitative development of Artemia Branchiopoda crustaceans in the small lakes of Pribalkhashye (№ 1-5) in July and at the end of August is quite considerable. At the same time the populations of Artemia at the end of September in lakes No. 4 and 5 are much more numerous, than at the end of July in lakes No. 1, 2 and 3. The median number of crustaceans in September for lakes № 4 and 5 exceeds that in lakes № 1, 2 and 3 in July. Also Artemia biomass raised five times at the expense of larger, mature crustaceans prevailing as a part of population by the end of summer. It is possible to tell that in September in the explored small lakes of Pribalkashye the third Artemia generation was observed. Assessing the biomass of Artemia in the lakes No. 1, 2, 3, 4 and 5 of Karabassky floods, according to the adopted characteristics [7, 13], itcan be inferred that lake No. 4 on the biomass indicators of Artemia – 29.96 g/m3 is highly productive. Lakes No. 1, 2, 3 of Karabassky floods (coastal) with biomass of Artemia 1,13, 1,12 and 2.91 g/m3, respectively, are low-productive reservoirs, lake No. 5 with biomass of 16.25 g/m3 are characterized of medium product.Despite considerable quantitative development of Artemia crustaceans, the density of the lakes which are freely floating cysts in plankton, was low and changed from 500 pcs/m3 in lake No. 1 up to 8 330 pcs/m3 in a coastal of lake No. 2. Their biomass at the same time fluctuated ranging from 5.0 up to 83.3 mg/m3 that corresponds to low indicators. In the literature it is indicated that the reserve of cyst depends on biomass of crustaceans and that cysts are more produced by the third Artemia generation [13]. The reserves of autumn plankton cysts of small, shallow-water lakes No. 4 and 5 of the Karabassky floods were calculated by the formula of the autumn plankton cysts.To evaluate the condition of Artemia crustacean and cyst populations in the small lakes of Pribalkhashye of the Karabassky floods, the comparison of their quantitative development to similar data of stocks relatively cysts of the salt lakes of North Kazakhstan in 2016 is carried out [9]. The quantitative indicators of Artemia of the lakes of the Karabassky floods and lakes of North Kazakhstan are presented in Table 5.Table 5Quantitative indicators of Artemia from the lakes of the Karabassky floods and lakes of North Kazakhstan ReservoirArtemia populationArtemia cysts in planktonArtemia populationArtemia cysts in planktonIndexexpl./m3g/m3expl./m³g/m3Indexexpl/m³g/m3expl /m³g/m3Karabassky floods (2021)Lakes of the North Kazakhstan region (2016)Lake № 11.791.130.500.005Ushsai2.71.791 792.217.922Lake № 215.6914.040.830.008Kalibek1.02.297428.64.286Lake № 36.362.912.500.025Mengisor4.00.170562.15.621Lake № 428.129.961.00.01Stanovoe10.011.558850.850Lake № 57.916.251.00.01Solenoe3.31.33174.90.749The quantitative development of Artemia crustaceans in lakes of the Karabassky floods is comparable with that in lakes of the North Kazakhstan area, perspective on cyst [4, 5]. Moreover, the indicators of number and biomass of Artemia in the lakes under study exceed the similar indicators of the North Kazakhstan reservoirs. But the cysts quantity in plankton of the lakes of the Karbassky floods is 2-3 orders is lower, than in the North Kazakhstan reservoirs. However, we calculated the expected reserves of autumn cysts in plankton for lakes of the Karbassky floods by the biomass of Artemia crustaceans of the third, August, generation made as it was specified earlier, 3.69 g/m2. This value is slightly smaller than the average reserves of cysts (5.19 g/m3) in the plankton lakes of the North Kazakhstan region in 2016, which indicates the perspective of the studied small reservoirs of the Pribalkhashye with respect to autumn plankton cysts.ConclusionIn the lakes Artemia crustaceans are presented by bisexual parthenogenetica race, with all age stages of development during the summer -autumnal period of observations. The hydrochemical mode of hypergaline lakes of the Karabassky floods is favorable for the activity of Artemia Branchiopoda crustaceans. The size of crustacean populations biomass in Lake Balhash changes on seasons ranging from low to very high. Lake No. 1 is highly productive in Artemia in the summer, and lake No. 2 - in the spring. Such difference in temporary aspect is caused by existence of various generations in the crustacean populations on seasons.